1. I have half playsand/half ee in my tank. My crabs rarely go on the sand side, & I always catch them digging around in the ee, so I assume they like it better. The problem is, I don't really like the ee. It gets all inside the extra shells in the tank and turns my sponges/light-colored shells a poopy brown color. However,it helps with keeping hum. levels high, so I think I need it or something like it. Anyone know of another similar product or a suitable substrate other than playsand or ee? 2. Approx. how often should a golf-ball size crab molt? My largest crab molted end of July/early Aug, and for the past 4 days has been buried at the bottom of my tank. Isn't it soon for him to be molting again?